On Positive Sasakian Geometry
نویسندگان
چکیده
A Sasakian structure S=(;;;;g) on a manifold M is called positive if its basic rst Chern class c 1 (F) can be represented by a positive (1;1)-form with respect to its transverse holomorphic CR-structure. We prove a theorem that says that every positive Sasakian structure can be deformed to a Sasakian structure whose metric has positive Ricci curvature. This allows us by example to give a completely independent proof of a result of Sha and Yang SY] that for every nonnegative integer k the 5-manifolds k#(S 2 S 3) admits metrics of positive Ricci curvature.
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